Leading Conservative rabbis gather in Las Vegas to 'rebrand' the movement, but there is little agreement about how to draw people back into synagogues.

Reporting from Las Vegas — Three hundred rabbis walk into a Las Vegas martini lounge. Bartenders scramble to handle the crowd — the rabbis are thirsty. Suddenly, an Elvis impersonator takes the stage.

We are faced with two possibilities.

One, this is the beginning of a joke.

Two, they don't make rabbis the way they used to.

The Rabbinical Assembly, the clerical arm of Conservative Judaism, would have you believe the second message, or something like it. That's why it launched its 2011 convention with a martini reception at a Las Vegas synagogue. The gathering was billed as an attempt to "rebrand" the Conservative movement, which has seen alarming declines in membership in recent years.

"We are in deep trouble," Rabbi Edward Feinstein of congregation Valley Beth Shalom in Encino told the convention the next day. "There isn't a single demographic that is encouraging for the future of Conservative Judaism. Not one."

Those words could apply equally to a number of U.S. religious denominations, especially liberal Protestant and Jewish faiths. Membership is falling; churches and synagogues are struggling financially; and surveys show robust growth among the ranks of those who declare no religious affiliation.

The situation may be especially alarming to the Conservative movement because it was, for many years, the largest denomination in American Judaism. It was the solid center, more traditional than Reform, more open to change than Orthodoxy.

A decade ago, roughly one of every three American Jews identified as Conservative. Since then, Conservative synagogue membership has declined by 14% — and by 30% in the Northeast, the traditional stronghold of American Judaism.

By 2010, only about one in five Jews in the U.S. identified as Conservative, according to the American Jewish Congress.

The Reform and Orthodox movements also saw declines, although not nearly as steep. Reform Judaism for a time claimed the most adherents, but today that distinction goes to people who identify themselves as "just Jewish," meaning they don't associate with any of the traditional denominations. Many are entirely secular.

"We're all in trouble," said Rabbi Julie Schonfeld, executive vice president of the Rabbinical Assembly and one of those trying to save the Conservative movement. Correcting herself, she said, "We're not in trouble, but we're in urgent need of rethinking the institutions of Jewish life."

Conservative Judaism has many strengths. It includes some of the most vibrant congregations in American religious life and some of the most prominent rabbis, among them David Wolpe of Los Angeles' Sinai Temple, Bradley Shavit Artson, dean of the Ziegler School of Rabbinic Studies, also in L.A., and Harold Kushner of Natick, Mass., author of "When Bad Things Happen to Good People."

But as the rabbis gathered at a Las Vegas resort — a relatively sedate spot far from the Strip — much of the talk was about the urgent need for change.

The movement's problems, many agree, begin with its name, which has nothing to do with political conservatism and doesn't accurately describe a denomination that accepts openly gay and lesbian rabbis and believes the Bible is open to interpretation. But that's just for starters.

Deep dissatisfaction with the organizations that lead Conservative Judaism prompted a number of influential rabbis in 2009 to demand urgent change, warning, "Time is not on our side." The group won promises of substantial change from the United Synagogue of Conservative Judaism, which represents Conservative congregations, and helped prompt reforms in the institutions that train and represent rabbis.

A similar revolt by prominent Reform rabbis preceded that denomination's continuing effort to reinvent itself, a project launched at L.A.'s Hebrew Union College last November.

So what does it mean for a religious movement to reinvent or rebrand itself?

"It's one thing for a corporation to say 'We're going to reinvent ourselves,'" said David Roozen, director of the Hartford Institute for Religion Research.

"Sometimes they get into another business," he said. "A religion … can evolve, it can be reinterpreted, you can express it in a slightly different style, but you can't just be doing Judaism one day and say 'I'm going to sell cars' the next."

The Conservative rabbis won't become car salesmen, but they batted around some fairly radical ideas and predictably stirred up some opposition.

There was talk of eliminating membership dues for synagogues or switching to a la carte "fee-for-service" plans — so that a parent who wants only to send his or her child to religious school won't also be paying to support the congregation's other programs. But some said dues give congregants a vital sense of ownership.

Wolpe, the Sinai Temple rabbi, said the movement needs a slogan, one that's short enough to fit on a bumper sticker. He suggested "A Judaism of Relationships."